What bug ... the bug from this thread ... Playgrounds can not run valid Swift code using XCode 13 Beta 5. Can @eskimo open a bug for it? Here just try this valid Swift 5.5 code in XCode 13 Beta 5 Playgrounds ... func doIt() async -> String {     let t = TimeInterval.random(in: 0.25 ... 2.0)     Thread.sleep(forTimeInterval: t)     return String("\(Double.random(in: 0...1000))") } async {     async let a = doIt()     async let b = doIt()     async let c = doIt()     async let d = doIt()     let results = await [a, b, c, d]     for result in results {         print("  \(result)")     } } I have no idea how to fix the code format. I guess we can not format code in a comment? :-(